It has been reported that optical artist Sadao Iizuka passed away on March 24 at age 88. Iizuka joined Eiji Tsuburaya's art department on the original Godzilla and first worked as an optical animator on The Mysterians. Among the many iconic animated visuals he went on to create were King Ghidorah's gravity beams, the rays emitted by the maser tanks and Ultraman's spacium beam, which he created for the original series and most recently animated again for Shin Ultraman.
Iizuka's Wikizilla page details his expansive portfolio of work: https://wikizilla.org/wiki/Sadao_Iizuka
A 303-page biography of Iizuka called "The Man Who Has Continued to Draw Rays of Light" was published in Japan back in 2016. Now there's a book that would be a revelation with an English translation!
https://www.amazon.co.jp/dp/4800308518
https://augustragone.blogspot.com/2016/01/the-man-who-continues-to-draw-ray-beams.html
https://www.tohokingdom.com/forum/viewtopic.php?t=24541
R.I.P. Sadao Iizuka